Use National ID for Canadian employees?

The password field default expression uses the last 4 of the SSN.

However, our Canadian employees use National ID.

Can we setup Connect to AD so that if it is a US employee, we use SSN and if it is a Canadian employee, we use National ID?

Try using NationalId instead of SSN:

Person.NationalId.Substring(Person.NationalId.Length - 4, 4)

The NationalId field always has a value, which is National ID for Canadian employees and Social Security Number for US employees.

Does this make sense?